Flow Stress Modelling and 3D Processing Maps of Al4.5Zn4.5Mg1Cu0.12Zr Alloy with Different Scandium Contents

Featured Application The constructed models may have potential application for the development of optimal hot deformation technologies of Al-Zn-Mg-Cu alloys. The hot deformation behaviour of an Al4.5Zn4.5Mg1Cu0.12Zr based alloy with 0.05, 0.1 and 0.15% Sc was investigated at temperatures between 300-450 degrees C and a strain rate of 0.1-15 s(-1). The materials constants of a flow stress model based on the Zener-Hollomon parameter were determined (AARE was 5.8%). Three-dimensional processing maps were established by combining power dissipation efficiency and flow stability diagrams. Based on processing maps analysis and microstructures investigations, the optimal deformation parameters were determined as a temperature range of 350-400 degrees C and strain rates of 0.1-1 s(-1) for the alloys with 0.05% and 0.1% Sc, and 0.1 s(-1) for the alloy with 0.15% Sc.